Evaluation of the precision in the dentifrice abrasivity measurements obtained by a radiotracer method

The radiotracer method was applied to evaluate the precision of the measure ments of abrasivity data obtained for dentifrice samples and for abrasive a gents (silica and calcium carbonate). This method consists of measuring P-3 2 transferred to a dentifrice or abrasive slurry when an irradiated dentin is submitted to a brushing simulation. Results obtained for abrasivity indi ces had good precision with relative standard deviations lower than 11.8%. Comparisons made between our abrasivity index data with those obtained at t he Oral Health Research Institute of Indiana University also showed a good agreement.